Arrested by the Ald, scholar Bon Ugane and merwoman Leki Borle find themselves on a prison ship bound for the island of Skythe - a barren land and the site of long-ago wars.

Warped and ruined by the ancient conflict, survival on the island is tough and its original inhabitants are neither friendly nor entirely still human. But something else waits on the island, a living weapon whose very existence is a heresy. Destroyed many years ago, it silently begins to clutch at life once more.